This season, a champion may finally emerge. Seven years in, and no American has completed the American Ninja Warrior course all the way through, from the regional city qualifier and final, through the three preliminary stages of the national final in Vegas, and up the 77-foot rope climb of the fourth and final stage, Mt. Midoriyama, just across the Strip from Mandala Bay. Over the past six seasons, the show has grown from a niche cable oddity to an NBC series that attracts five million viewers every week, a meteoric rise that I'll divide roughly into three eras: Japan-o-Mania, The Transition, and Viva Las Vegas.

Japan-o-Mania: 2009-2011 (Seasons 1 – 3)

Though American Ninja Warrior premiered more than a decade after its predecessor, Japan'sSasuke (pronounced sauce-kay), the American version heavily reflected its parental influence during the first three years. Almost all of the obstacles were direct imports from Japan, and, after the regional qualifier, final, and a Survivor-style "boot camp," the ten highest-performing American ninjas flew to Japan to compete on the Sasuke course.

The major difference between the two shows was that the Japanese ninjas had to complete the course in a certain amount of time, and any or all or none of the 100 competitors could advance from stage one to two. In the American version, the top 30 advanced regardless of their speed. The courses were also slightly different. In Sasuke, stage two was entirely new, while on the American course, obstacles were simply added to stage one.

In comparison with later eras, the first three seasons attracted a relatively small pool of competitors. The first year, hopefuls could only compete in Los Angeles (the last time a qualifier would be held there), and for the next two years, only in Venice Beach (which has held a qualifier ever since). In addition, G4 , which later re-launched as the Esquire Network, only broadcast 12 hours of ANW the first season and 18 the next; by comparison, last season ran for 26 hours. Limited both by geography and visibility, the show featured mostly amateurs in comparison to the ninjas we'd see in later seasons.

From the very beginning, though, the general structure of the qualifying course was more or less apparent. The Quintuple Steps open, followed by a jolt and a balance test. Then, it's two upper-body obstacles (usually one that's grip strength-intensive) and the Warped Wall.

The Transition: 2012 (Season 4)

In the fourth season, ANW begins to transition from zany pastime to serious sport. In addition to Venice Beach, Dallas and Miami each hosted two regional qualifiers. The details of the ninja course had always been kept a secret, so to eliminate any unfair advantages for the ninjas at qualifiers later in the season, all three cities had different obstacles (apart from the two constants: the Quintuple Steps at the beginning and Warped Wall at the end). As a result, the ninja universe greatly expanded.

Likewise, competitors became more intense. It seemed like everyone and his brother (and his doctor and his stepfather) were building course replicas in their backyard. Ninjas like Sean Morris started combining personality with genuine talent, and after three years, veterans were emerging with their own intriguing storylines. Drew Drechsel had an impressive comeback narrative after he tore his ACL and MCL on the Half-Pipe Attack in Japan the previous year—not only did he return (and make it to Vegas), but he recruited Joyce Shahboz, his physical therapist, to compete as well.

But the transformation was not complete. Even though Mt. Midoriyama moved to Vegas in 2012, and competitors no longer traveled to Japan, I believe that the fourth season cannot be considered part of Viva Las Vegas for this one reason: most of the regional qualifiers were still held during the day, a seemingly trivial but critically important point.

It's obvious that the show both is fairer when run at night and looks more epic (compare Miami's qualifier that year to the one in Dallas). The stadium lights produce more saturated colors and eliminate the potential issues caused by shadows and the sun. Filming after sunset, though, is a logistical nightmare. Temperatures drop. Fans fall asleep. The crew becomes nocturnal. But more importantly for the history of ANW, the athletes must now adapt. When season five comes around, no longer is competing on American Ninja Warrior a silly thing to do on a whim one weekend. It's a grueling, Circadian-rhythm-busting commitment. When the producers decided to film exclusively at night, they took ANW to the next level—the Vegas level.

Viva Las Vegas: 2013 to present (Season 5 – 7)

By 2013, ANW was truly a national competition. Four cities hosted regional qualifiers that year, then five the following year, and six for this upcoming season (though the San Diego course is open only to military veterans and active servicemen and women). Thousands submit audition tapes for the 100 or so spots in each city, and hundreds camp out before the competition with no guarantee that they'll run, sometimes for more than a week (the rumor in Kansas City was 10 days).

As more locations are added, competitors' training has to keep up. Each additional regional city means eight more obstacles (four for the qualifier and four for the final), which means ever more training possibilities for the following year. As a result, those handmade backyard courses have transformed into professional gyms such as Chicago Ninja Academy, which have full-scale replicas of all but the most elaborate obstacles (like the Spider Climb).

The obstacles are also more difficult. Take the Cargo Net, for instance. Unlike previous seasons, when a ninja could go over the net (0:30), the more recent courses are designed for competitors to go underneath, requiring more time and energy. As the series has progressed, the net has also hung closer and closer to the water, another subtle but crucial detail. Flip Rodriguez, ANW veteran since 2011, misplaced his toe (0:35) in the 2014 Venice qualifier, and just like that, the "face of Miami hit the water" (considering that Flip competes wearing a white mask, it's unclear whether commentator Matt Iseman's pun was intended or not).

Will this be the year an American Ninja Warrior is crowned? With a grand-prize of $500,000 at stake, all eyes are on the top of Mt. Midoriyama. Brian Arnold is perhaps the most widely publicized ninja to quit his job in order to train, but it's likely that many more have (or take a disturbing number of sick days). Every year attracts a larger and stronger pool of contestants, but perhaps more than in any other sport, the history of "American Ninja Warrior" is one of stunning upsets.

Small, almost imperceptible, mistakes can end an otherwise flawless run. In addition to Flip's foot slip on the Cargo Net, I've watched Ben Wicks (1:39) at the 2012 Dallas finals at least a dozen times, and I'm still wondering what went wrong on Cycle Road (as I'm sure he is, too). Brent Steffenson, the most accomplished American ninja in 2012 (and the only person to clear stage two of Mt. Midoriyama at the time), didn't even make it to the 2014 Dallas finals (1:30). Therefore, who will win—if anyone—is impossible to predict, but here are a few things to watch for:

Seamless Q Steps. Typically, how a ninja handles the Quintuple Steps is a decent indicator of her ability and preparation. But style only counts for so much, as a run may be inelegant but successful.

Arms at 90. It's somewhat counterintuitive, but the obstacles are easier with bent arms. When competitors fall into a dead-hang (1:24), it's a foreboding sign.

The Peg Board. Of all the obstacles, this is, in my opinion, the most seemingly easy-looking. Competitors seem to glide across it (2:08), but the technique is brutal: you have to hold your entire body weight on one arm that's (ideally) at 90-degrees while also reaching with the other arm and inserting a peg.

Season seven will not disappoint. Whether you watch for the wipeouts, the veterans, the obstacles, or the spectacular bodies, you'll want to tune in to NBC on Mondays at 8/7c.